This invention relates to slippers having improved resistance to tearing which are formed from foamed synthetic polymeric or elastomeric sheeting. More particularly, the invention relates to a scuff type slipper which exhibits improved tear resistance at the rearmost point where its upper member is joined to its sole member. An improved method and an apparatus for making such a scuff slipper also comprise a part of this invention.
In the past, there has been a need for strong, sanitary and inexpensive footwear and for efficient methods and apparatus for manufacturing such articles. To a substantial extent, U.S. Pat. No. 3,238,079 has met this need by disclosing a slipper which is held on the wearer's foot by internal elastic tension in the slipper material. These slippers show a surprising degree of resistance to tearing of the material. Similarly, U.S. Pat. No. 3,793,746 discloses somewhat different types of slippers of the heel gripping and scuff types, which were developed with a view toward minimizing tearing at the rearmost location where the upper member of the slipper is joined to the lower member. Although slippers made in accordance with this latter patent exhibit improved tear resistance relative to prior art devices, it has been found that lateral tearing may occur at the location mentioned, especially in the larger sizes. Since such slippers are frequently used by institutions where their low price may be outweighed by a high failure rate, a need exists to develop such slippers which will exhibit satisfactory resistance to tearing in all sizes.
In addition, the above slipper types usually require the use of one or both hands of the wearer to don the slipper. In the instance of the slippers of U.S. Pat. No. 3,238,079, the use of the hands is required since the foot opening in the upper member of the slipper must be stretched somewhat to permit the foot to enter. The slippers of U.S. Pat. No. 3,793,746 require the use of the hands to slip the toe of the foot into the rather small foot-receiving pocket and to slip the heel of the foot into the heel-gripping portion. Even where no heel-gripping portion is provided, the use of the hands is required due to the rather small foot-receiving pocket. The slipper material adds to these difficulties since it is not at all slippery, but rather tends to resist sliding motion of the foot into the slipper. These characteristics have the desirable effect of tending to retain the slipper on the wearer's foot; however, for persons who for some reason are unable to reach their feet or may do so only with considerable discomfort, these prior art slippers are not entirely satisfactory. Thus, a need exists for simple, inexpensive, sanitary slippers having a design which permits the slipper to be donned without the use of the hands and to be worn without undue premature failure of the slipper material.